Craven r



(No Model.

0. R. 0RD.

AIR PUMP GOVERNOR. No. 442,492. Patented Dec. 9, 1890.

WITNESSES //v VEN 7'0/7 W MQwA B) 412. 5 J/MM alga, ATTORNEYS NlTESTATES PATENT OFFICE.

CRAVEN R. 0RD, OF MONTREAL, CANADA.

AIR-PUMP GOVERNOR.

SPECIFICATION forming part. of Letters Patent No. 442,492, datedDecember 9, 1890. Application filed April 4, 1890. Serial No. 346,605.(No model.)

To aZZ whom it may concern:

Be it known that I, CRAVEN R. 0RD, of Montreal, in the Province ofMontreal and Dominion of Canada, have invented a new and ImprovedAir-Pump Governor, of which the following is a full, clear, and exactdescription.

The invention relates to governors for airbrakcs; and its object is toprovide a new and improved governor which is simple and durable inconstruction and very effective and posltive in operation.

The invention consists of certain parts and details and combinations ofthe same, as will be hereinafter fully described, and then pointed outin the claims. Reference is to be had to the accompanying drawing,forming a part of this specification, in which the figure represents asectional side elevation of the improvement.

The improved air-pump governor A is provided with a suitably-constrnctedcasing B, having a steam-inlet 0, connected by the port I) in thepartition I) with the steam-outlet l leading to the pump. Thesteam-inlet C 1s connected in the usual manner with the boiler. The portD is adapted to be closed by thered uced end F of a cylindrical mainvalve l, fitted to slide freely in the cylinder G, formed on the casing13.

The upper part of the cylindrical main valve F is made hollow and isadapted to receive one end of a coiled spring II, pressing with itsother end against a plug l, screwing in one end of a cylinder J,somewhat less in diameter than the cylinder G, but arranged into linewith the latter. The cylinder J is formed in a casing B, screwing intothe main casing B, as is plainly shown in the drawing. The upper end ofthe cylinder J is formed with a valve-seat adapted to be closed by anauxiliary valve K, held on a reduced end K of a valve-stem K fitted toslide in the cylinder L, formed in the upper part of the casing B andsomewhat less in diameter than the cylinder J, previously mentioned.

The cylinder J is connected by a port a with the steam-inlet C, and thelower part of the cylinder L is connected by a port Z) with the upperend of the cylinder G. The upper end of the val ve-stem K extends into achamber N, formed in the extreme upper end of the casing B, and in thesaid chamber is held adisk 0, against the under side of which abuts theupper end of the valve-stem 1' The disk 0 is secured on the lower end ofa stem 0, and on the top of the said disk is arranged a diaphragm P,held in place on the said disk 0 by a nut 0 screwing on the stem 0.

The diaphragm P is held in place in the chamber N by a cap B screwinginto the upper end of the casing B. The stem projects into this cap Band also into a cap Q, screwing 011 the cap B and provided at its upperend with an opening Q, coni'iccted with the air-pipe of the air-brake onwhich the device is to be applied. The upper end of the stem 0 is quiteslack in the opening Q, so that the air passes down into the cap B whereit presses on the top side of diaphragm. P.

On the stem 0 is a coiled spring R, which rests with its lower end onthe cap 13 and with its upper end against the under side of a nut S,screwing 011 the stem 0 and locked in place by a jam-nut S. The lowerpart of the chamber N is connected by an opening N with the outside, thesaid opening serving as a drip for any water of condensation which mayaccumulate in the chamber N.

The operation is as follows: The device, as illustrated in the drawings,shows the diaphragm P when it is depressed by air-pressure applied onits top side, which comes down through the opening Q. The auxiliaryvalve K is thereby pushed off its seat in the upper end of the cylinderJ, so that live-steam from the inlet 0 can pass through the port a intothe cylinder J, and from the latter past the auxiliary valve K into thelower end of the cylinder L, from which the steam passes into the portI) and into the upper end of the cylinder G to press the main valve Fdownward, so that its reduced end F closes the port D, thus shutting offcommunication between the inlet 0 and the outlet E. It is understoodthat the total pressure on top of valve F is greater than the totalpressure on the bottom, owing to the spring II and the weight of thevalve, which keeps the pressure greater on the inlet side than on theoutlet, and the initial pressure on the shoulder, or that. port-ion ofthe valve which does not cover the portD, being less than the initialpressure which acts on the top of the valve, the total pressure on thebottom will be less than the total pressure on the top, so that thevalve starts and moves downward toward its seat as soon as the auxiliaryvalve K is pushed'oft its seat by the diaphragm. Now as this main valveapproaches its seat the opening through the port D is reduced, so thatthe volume of steam will be slightly checked and the press 11 re on theoutlet side thereby lowered, and at the same time the pressure acting onthe shoulder, or that portion of the valve which does not cover theport, will be also lessened, and consequently the downward movement ofthe valve is accelerated until the valve reaches its seat. \Vhen thevalve has finally reached its seat and the port thereby closed, thepressure is only on the extreme lower end, or that portion of the valvewhich covers the port, and its area being less than the whole. top areaof'the valve, the valve will be firmly held to its seat until thepressure on the top is reduced. The moment the air-pressure is reducedor taken off the spring R draws the stem 0 and the diaphragm P upward,sothat live steam entering the cylinder J through the port a seats theauxiliar valve K, thus shutting off the communication of the cylinder Jwith the port 1), leading to the cylinder G. The steam pressure in theinlet 0 now acts on the reduced end F of the main valve, so that thelatter slides upward and the port D is opened to establish thecommunication between the inlet 0 and the outlet E. It will be seen thatwhen the auxiliary valve K is closed by a reduction of the air pressureon the diaphragm P then the steam confined in the upper end of thecylinder G reduces the pressure gradually by escaping between the sidesof the main valve F into the outlet E, so that this reduced pressure,together with the pressure of spring H, will at last be overcome by thesteam-pressure in inlet 0, which will force the main valve F upward andopen the port D.

Having thus fully described my invention, I claim as new and desire tosecure by Letters Patent 1. In an air-pump governor, the combination,with a passage-way provided with a partition having a port therein and acylinder opening into the outlet, of a valve fitted to slide freely inthe said cylinder and adapted to close the said port, the portion of thevalve which closes the port being of less cross-sectional area than thepart fitting in the cylinder, a spring acting on said valve to retainagreater pressure on the inlet than on the outlet side, and an auxiliaryvalve operated by steam to the firstuamed valve, substantially asdescribed.

2. In an air-pump governor, the combination, with a passage-way providedwith a partition having a port therein and a cylinder opening into theoutlet and communicating through ports with the inlet, of a valve fittedto slide freely in the cylinder and having its lower end, which closesthe port, of less crosssectional area than the part fitting in thecylinder, a spring acting upon the upper end of the valve, and anauxiliary valve for closing the ports leading to thesaid cylinder, saidauxiliary valve being operated by airpressure, substantially as hereinshown and described.

In an air-pump governor, the combination, with a passage-way divided bya partition having a port therein, a cylinder above the port and openingint-o the outlet side of the passage-way, and a second cylinder of lessdiameter than the first-named cylinder and communicating therewith andwith the inlet of the passage-way, of a spring-pressed valve in thefirst-named cylinder and adapted to close the port of the passage-way,an auxiliary valve in the second-named cylinder and adapted to establishand close communication between the inlet of the passage-way and thecylinder containing the springpressed valve through the cylinder of theauxiliary valve, and a diaphragm adapted to be acted upon byair-pressure to operate the auxiliary valve, substantially as hereinshown and described.

4. In an air-pump regulator, the combination, with the spring-pressedstem 0, provided with the diaphragm P, adapted to be acted upon byair-pressure,of a passage-way divided by a partition having a porttherein, the cylinder G above the port and opening into the outlet ofthe passageway, the spring-pressed valve F F in the cylinder, thecylinder J above the cylinder G and connected by port a with the inletof the passage-way and provided with a valve-seat, the cylinder L,connected by port I) with the cylinder G, and the I auxiliary valve K,provided with the stern K having the reduced portion K and adapted to beengaged by the lower end of the stem 0, substantially as herein shownand described.

CRAVEN R. 0RD.

Witnesses:

WALTER BIRD, GEORGE HEDGE.

